Need help with Minecraft server admins

I have recently set up a Minecraft server. Only I have a problem with OPing people. Whenever I OP someone in the folder (ops.json) then load up the server (.exe) and enter Minecraft, it resets and the OP's wont stay. Help!


Do not OP a player using The JSON File type because in a JSON File you cannot have any indentation and everything needs to be specific. So i reccomend OPing People Using The OP Command In The Console.

Usage

/op <username>